During the process of video and image editing, one alters portions or all of a video image, e.g. by moving an image from one portion of a screen to another, rotating the image, expanding the image or shrinking the image. Other common image manipulations include warping an image (i.e. deforming the image in three dimensions), magnifying parts of an image, performing cylindrical, spherical, hyperbolic, or parabolic transformations to the image (e.g. causing a two-dimensional image to appear to bend or wrap around a cylindrical, spherical, hyperbolic or parabolic surface), melting images, etc. Parabolic transformations may be used to provide a three dimensional (3-D) effect.
Frequently, the image to be manipulated is in the form of a pixel array. In other words, the image is stored as an array of data values, each value corresponding to the color and brightness of a small area of the image. When performing the above-mentioned video image manipulations, one typically performs calculations to transform every pixel of the image. For example, for each pixel of the image, one performs calculations to determine a new location for that pixel on a video screen. Large images can contain millions of pixels. Further, for the case of image streams (e.g. as in the case of video images), dozens of frames per second must be transformed. Thus, many millions of pixels may have to be analyzed and modified for each transformation in a very short amount of time. Such transformations require either enormous CPU resources or special hardware to be able to transform large numbers of pixels in a short amount of time.
Although some 3-D video standards are already developed and have, for example, been included in the Motion Picture Experts Group 4 (MPEG4) video standard, these standards require specialized transmission systems, players, etc., which may not be installed into common commercial video broadcasting systems for a long time.
In addition, the amount of data transmitted in real 3-D video broadcasting on a regular basis is so large that it can be overwhelming for present-day delivery systems and for systems anticipated in the near future.
Furthermore, 2-D television broadcasts include 2-D advertisements that are not viewer specific. For example, the advertisement may be nationally broadcast, but not localized to a specific viewer or localized group of viewers.